342 



HEPATIC VESSELS AND LOBULES. [sect. 159. 



Fig. 147. 



be divided into several distinct lamellae. If the capsules, or, as 

 they mi^lit be still better called, the septa of the lobules, be 

 followed, it is found that they are chiefly expansions of the areolar 

 tissue accompanying the vena porta, etc., or of the so-called 

 capsule of Glisson, although they are also connected with the 

 serous covering of the liver, and adjoin the larger hepatic veins. 

 Kiernan was the first to comprehend and express correctly the re- 

 lation of the lobules to the hepatic vessels, when he said, that they 

 sit upon the branches of the hepatic veins like leaves upon their 

 stalks. In fact, it is found, when a smaller branch of the hepatic 

 vein is cut open (fig. 146, b b), that it is surrounded on all sides by 

 hepatic lobules, and receives a vein from each of them, so that 

 they really appear to be attached to it by short stalks. 



Now, since the same arrangement exists in the veins of medium 

 diameter downwards, as far as the venae intralobulares, the hepatic 



veins and lobules may, not 

 without reason, be compared 

 to a tree, whose branches 

 are so numerously and closely 

 beset with polygonal leaves, 

 that the foliage, so to speak, 

 constitutes only one mass. 

 If, now, it be imagined that 

 another ramified vascular sys- 

 tem is interpolated from above 

 into the tree of hepatic veins, 

 so that its larger branches 

 penetrate into the clefts be- 

 tween the main divisions, and 

 the smaller and smallest into 

 the interstices of the subor- 

 dinate segments and the lo- 

 bule, and in such a manner, 

 that each lobule is on many of 

 its sides in contact with the finest branches, and receives a coat 

 from the connective tissue accompanying them, we have obtained 

 as definite an idea as is possible of the relations of the portal vein. 

 With regard to the gall-ducts and the hepatic arteries, they simply 

 accompany the portal vein, and require, accordingly, no further 

 mention. The form of the lobules is, in the pig's liver, angular, so 

 that, when viewed in longitudinal and transverse sections, they 

 generally form irregular four, five, or six-sided figures. 



^»5 



Branch of the portal vein of the pig cut open, 

 with the branches of the hepatic artery and duct 

 accompanying it. After Kiernan. 



